#include <stdio.h>
int isPrime(int n) {
    if (n <= 1) {
        return 0;
    }
    for (int i = 2; i * i <= n; i++) {
        if (n % i == 0) {
            return 0;
        }
    }
    return 1;
}

int main() {
    int even;
    printf("请输入一个充分大的偶数：");
    scanf("%d", &even);
    
    if (even % 2 != 0 || even <= 2) {
        printf("请输入充分大的偶数！\n");
        return 1;
    }
    
    int found = 0;
    for (int i = 2; i <= even / 2; i++) {
        if (isPrime(i) && isPrime(even - i)) {
            printf("%d = %d + %d\n", even, i, even - i);
            found = 1;
            break;
        }
    }
    
    if (found) {
        printf("验证成功，该偶数可以表示为两个素数之和\n");
    } else {
        printf("验证失败，该偶数不能表示为两个素数之和\n");
    }
    
    return 0;
}